In light of the pilsner discussion below, I got to wondering about yeast, fermentation etc. Now clearly, lagers take quite a bit longer to condition than ales, and part of the reason is because primary fermentation takes much longer. So, what if one pitched both lager and ale yeast? The primary would be done at ale temps, and would finish much faster because ale yeast would do most of the work. The beer would then be brought down to lager temps to allow for the lager yeast to "clean up" the beer and condition it out.

I have used both in my beer before, especially if I am not sure if I can keep a constant temp, I do use compatible yeasts though. Use a clean ale yeast if you are going to attempt this. If you are considering lager yeast, you must be after the crisper taste.